Multiple telephone connecting device



Jan. 5, 1932. G. D. MANSFIELD 1,839,795

MULTIPLE TELEPHONE CONNECTING' DEVICE Filed April '7, 1951 /70 30INVENTOR.

yatented Jan. 5, 19332 erre STATES GEORGE D. IvANSFIED, OF PHILDELPIA,PENNSYLVANIA MULTIPLE TELEPHONE CoNNncfrINs DEVICE' Application ineaApril 7,

My invention relates to a new and useful multiple telephone connectingdevice whereby any desired number of telephones from correspondingexternal point-s may be interconnected extraneously. to the telephoneswitch board of an office so that the persons using said telephones maycarry on a conference or multi-lateral conversation.

1t is at present possible to accomplish this result by connecting aplurality of telephones to an open switch board but'this practice,

particularly if applied to an automatical telephone switch board willrender the switch board practically useless and inoperative for otherpurposes throughout the duration of the conference.

It is therefore further an object of my invention to produce aninterconnecting device whereby a. plurality of office extensions or aplurality of telephones from corresponding and remotely situated oicesmay be interconnected to carry on a conference or multi-lat-V eralconversation without in any way interfering with the normal operation ofthe switch board.

|The structure and assembly of my device will be apparent from thefollowing description taken in connection with the accompanyingvdrawings in which:

Fig. 1 is a plan View with the casing removed to show the internalwiring diagram.

Fig. 2 is a section on line 2-2 of Fig. 3 showing details ofconstruction.

Fig. 3 is a section on line 3-3 of Fig. 2 showing details ofconstruction.

Fig. 4 is a View of a telephone plug or jack of the type usuallyemploy-ed for plugging in lines on a switch board. f

Before describing the invention in detail it may be well to point outthat the present invention is intend-ed to perform the same result-sproduced by thedevice disclosed in my Patent No. 1,799,916 issued April7th, y1931 and in addition to provide in a single device, means forpermitting conference or multilateral conversation.

Referring to the drawings in which like reference characters indicatelike parts, 1 designates a suitable casing for housing the device whichcomprises the front wall 2, the

1931. Serial 170.528,263.

side walls 3 and the rear wall 4. In the front n wall 2 are secured thecorresponding pairs of metallic sleeves 5, 6 and 7 of which any desirednumber may be provided. The pairs ofnietallic sleeves 5, 6 and 7 carrycorre- 55 .spending pairs of metallic brackets 8, 9 and 10 each of whichcarries contact elements 11, 12 and 13, 14, 15 and 16 and 17, 18 and 19respectively whichare deflected at their front ends as at 20. Thecorresponding pairs of 6 contact elements 12, 15 and 18 are providedwith the `lugs 21, and the contacts 11 to 19 inclusive are secured bythe screws 22 and are insulated as at 23. The corresponding pairs I ofContact elements 14 and 15 are electrically 65 inter-connected in seriesby the continuous wire 26 and the corresponding pair of contacts 14 arecross-connected by the wire 27. Similarly, the corresponding pairsofcontact lelements 12, 15 and 18 areelectrically inter- 70 connected inseries by the continuous wire 28 ,whilev the pairs of contact elements15 are cross-connected by the wire 29. The corresponding pairs ofcontact elements 13, 16 and 19 are inter-connected in series by thecontinnous wire and the pair of contacts 16 are cross-connected by thewire 31. 33 designates jack or plug at the end of the telephone wire34and is adapted to be inserted through the metallic sleeves 5, 6 and 7 sothat 8 the contactportion 35 of the jack 33 is engaged by the front endportions of the contact elements 11, 12, 14, 15 and 17 and 18.

1 The operation is as follows: If it is desired to inter-connect twotrunk lines, extraneous 8 to the switch board to each other through themedium of the switch board as set forth in my Patent No. 1,7 99,916aforesaid) it is nierely necessary to plug the jacks 33 of the de siredtrunk lines into any corresponding pair of sleeves 5, 6 or 7. If it isdesired to interconnect more than two telephones whether or not suchtelephones are connected to trunk `lines extraneous to the switch-board(incoming calls) or whether it is desired to connect extraneous trunklines to connection lines leading from the switch board to extensions invarious ollces, it is merely necessary to plug the acks 33 of thevarious telephones to be connected into corresponding pairs of thesleeves 5,6 and 7 and persons using said telephones will be able to heareverything said by anyone of them and to talk to any one who is soconnected. All this is done extraneously to the switch board and withoutinterfering with its normal operation. The screws 22 are insulated bythe insulating sleeves 34 so that electrical contact throughk the screws22 is established only between the contact elements l() and 19 as willbe best understood from Fig. 5.

Having thus described my invention what I claim as new and desire tosecure by Letters Patent, is

A device for inter-connecting a plurality 'of telephones ythrough themedium of a switch board but Without interfering with the nor- 'maloperation thereof which consists. of. a

support having a plurality of corresponding pairs of metallic sleevesadapted toy receive the corresponding Lpairs of telephone jacks,

,corresponding metallic brackets carried by said sleeves, andcorresponding electrical contacts carried by said brackets in insulatedrelation to leach other, the rear ends of said electrical contacts beingconnected to each other and in pairs.

GEORGE n. MANSFIELD;

